Loading dock lifts have a variety of applications involving the transfer of cargo between an elevated truck bed and a depot floor. A typical loading dock lift includes a lift platform and apparatus for moving the lift platform between an upper position aligned with a truck bed and a lower position in which the lift platform is aligned with the depot floor (e.g., non-movable floor). Cargo transfers during loading and unloading operations from the truck occur at a first side (e.g., the truck side) of the lift platform which is closely adjacent to or aligned (e.g., coplanar alignment) with the truck bed when the lift platform is in the upper position. When the lift platform is at a lowered position, cargo can be transferred between the depot floor and the lift platform at a second side (e.g., the depot side) of the lift platform, the side opposite from the truck side.
Generally speaking a lift platform is useful in elevating cargo from the depot floor to an upper level corresponding to a truck bed level to facilitate the transfer of freight onto the truck bed. That is, when freight is to be loaded onto a truck, the freight is transferred onto the lift platform over the depot side at the ground or factory floor level. Then the lift platform and any cargo loaded on the lift platform elevates until the lift platform comes into an essentially coplanar alignment with the truck bed whereby cargo can transfer to the truck bed past the lift platform at the truck side.
During an off-loading operation, an empty lift platform elevates to be in an essentially vertical alignment with the truck bed whereupon cargo can be moved from the truck bed onto the elevated lift platform past the truck side. Then the lift platform lowers to the factory floor level whereupon the cargo can be moved from the lift platform to the depot floor at the depot side of the lift platform.
Personnel may ride on a loading dock lift during movement of the lift platform. Consequently it is important that such loading dock lifts minimize the possibility of a person's sustaining an injury by making a misstep and possibly falling from the lift platform in an elevated position.
A need exists for safety barriers that close when the lift platform is in the upper position. A further need exists for the safety barrier to open and close automatically when the lift platform moves between the bottom position and the upper position, respectively.